Atheists... why do you believe that God doesn't exist?

[Rampant.A.I.]

The real problem, if you want to try and address it, is that god cannot be disproven ... which is frustrating for the atheist who wants to dismiss it.

I think the frustration is from the fact that god cannot be proven, and therefore the claim that he cannot be disproven is used to try to settle the matter. I think that in our day-to-day lives, for anything other than god and sports, we are willing to dismiss things that we cannot prove or disprove (I'm looking at you, "clutch hitting"). While the references to things like Santa Claus or unicorns are made semi-seriously, they do show that most of the time we easily reject such ideas on the basis that if you can't prove it, I don't need to treat it as anything but a myth.

As you say, he has no problem rejecting unicorns and leprechauns as myth, but doesn't seem to have any method to distinguish those mythological creatures from his mythological creature.

Frodo himself is guilty of the same dismissal of entities with no evidence, except his deity is protected by lapse in reasoning where it suddenly had to be disproven.

It's a simple reversal of burden of proof, due to cognitive dissonance, and the same magical thinking demonstrated by every superstitious belief in the supernatural worldwide.